A variety of bicycle frames and frame components have been described, including those described in, for example: U.S. Pat. No. 4,923,203 in the name of Trimble et al.; U.S. Pat. No. 5,213,322 in the name of Enders: U.S. Pat. No. 4,067,589 in the name of Hon; U.S. Pat. No. 5,011,172 in the name of Bellanca et al.; U.S. Pat. No. 4,550,927 in the name of Resele; U.S. Pat. No. 4,548,422 in the name of Michel et al.; U.S. Pat. No. 3,533,643 in the name of Yamada; U.S. Pat. Nos. 5,016,895 and 4,923,203 in the name of Hollingsworth; and U.S. Pat. No. 4,565,383 in the name of Isaac; each of which is hereby incorporated by reference in its entirety for the material disclosed therein. International patents containing pertinent disclosure include Italian Patent No. 448,310 in the name of F. Janecek; French Patent No. 895,046 in the name of Delorge et al.; and U.K. Patent No. 19,193 in the name of Otto Schonauer; each of which is hereby incorporated by reference in its entirety for the material disclosed therein.
These patents generally describe traditional bicycle frames could be constructed from tubing that was round in cross section. Such traditional round tubing frames typically consisted of two main triangle shapes. The larger of these two triangle shapes, referred to herein as the front triangle, consisted of a seat tube, a top tube and a down tube which were welded or adhesively joined to appropriate lugs (such as a head lug and bottom bracket lug). The bicycle frame could be constructed by laying up composite pre-preg into a female mold to produce a monocoque frame. Two smaller triangle shapes were employed, referred to herein as the rear triangles. Each consisted of a seat stay, a chain stay and a seat tube which was shared with the front triangle. The rear triangle assembly, when viewed from the side, appeared to be a single triangle, but when viewed from the top or rear, actually was two spaced apart rear triangles each terminating at its rear in an axle drop-out for mounting of a rear bicycle wheel.
Filament wound tubing has been constructed and articles made therefrom. If it was desired to manufacture a bicycle frame using filament wound tubing, then typically individual tubing members (which were round in cross section) would be constructed and then joined to aluminum cast lugs and more recently to composite lugs. Composite tubing used in conventional tube and lug frames has largely been produced using carbon/epoxy or graphite/epoxy pre-preg and roll wrapping process. Alternatively, a hollow bicycle frame could be made from square tubing using a lay-up, braiding process. The reader""s attention is directed to U.S. Pat. Nos. 5,215,322 and 4,923,203 for general disclosure. It was also known that bicycle frames or portions thereof could be made by injection molding. For general reference the reader is directed to U.S. Pat. Nos. 5,011,172 and 4,067,589.
There is a need, however, for bicycle frames and other components manufactured by a filament winding process so that the resulting product is light weight, strong, attractive, and cost efficient to manufacture. Similarly, there is a need for composite bicycle forks that are light weight, strong, attractive, and cost efficient to manufacture. The present invention meets these and other needs.
The present invention relates to net shape filament winding manufacturing processes and products that can be made using such processes. Products that can be made by the invented processes include, for example, bicycle frames, bicycle frame components, and components of other vehicles. In one aspect, a frame for a wheeled vehicle is provided. The frame includes a front structural element having a top beam, a down beam and a seat beam that are connected. The frame also includes an upper rear structural element having a left seat stay beam, a right seat stay beam, and a mounting portion configured for mounting to the front structural element. The mounting portion is typically formed by a joining of the left seat stay first end and the right seat stay first end. The frame can also include a lower rear structural element including a left chain beam, a right chain beam, and a mounting portion configured for mounting to the frame. The mounting portion is formed by a joining of a left chain stay first end and a right chain stay first end. The upper rear structural element is joined to the lower rear structural element left chain stay. The upper rear structural element is typically mounted to the front structural element by a shock absorption mechanism.
The upper and lower rear structural elements can be joined at wheel drop outs.
The front structural element and/or the rear structural element can be made of a resin matrix and reinforcing fiber. The front structural element and/or the rear structural element can be a filament wound composite.
The frame can also include a head tube and a head cap that joins the head tube to the front structural element. A seat tube can be joined to the front structural element by a seat cap. A bottom bracket tube can be joined to the front structural element and/or the rear structural element.
The frame can optionally be reinforced with reinforcing side elements mounted to a side of the front structural element. A channel can be formed in any portion of the front structural element and/or the rear structural element, and a reinforcing side element installed in the channel.
In a certain embodiment, the frame includes on its left side, a left seat beam channel on the left side of the seat beam; an elongate reinforcing member installed in the left seat beam channel; a left top beam channel on the left side of the top beam; an elongate reinforcing member installed in the left top beam channel; a left down beam channel on the left side of the down beam; an elongate reinforcing member installed in the left down beam channel; a left seat stay channel on the left side of the seat stay; an elongate reinforcing member installed in the left seat stay channel; a left chain stay channel on the left side of the chain stay; and an elongate reinforcing member installed in the left chain stay channel. In the same embodiment, the frame includes on its right side, a right seat beam channel on the right side of the seat beam; an elongate reinforcing member installed in the right seat beam channel; a right top beam channel on the right side of the top beam; an elongate reinforcing member installed in the right top beam channel; a right down beam channel on the right side of the down beam; an elongate reinforcing member installed in the right down beam channel; a right seat stay channel on the right side of the seat stay; an elongate reinforcing member installed in the right seat stay channel; a right chain stay channel on the right side of the chain stay; and an elongate reinforcing member installed in the right chain stay channel. The frame also can include a track configured to accept a cable. The track can be included in a channel in the frame in, for example, the upper and/or lower rear structural element.
In a certain embodiment, any structural element of the frame can include a first thickness of resin matrix and reinforcing fiber, a second thickness of structural foam, and a third thickness of resin matrix and reinforcing fiber. Any structural element also can include a channel in the structural foam with a reinforcing side element installed in the channel. A track can also be included in the channel to accept an elongate cable. The first and/or third thickness can be formed of resin matrix and reinforcing fiber, such as by filament wounding.
In other embodiments, a structural element having a top, a bottom, a first flank and a second flank is provided. The structural element includes a first thickness of resin matrix and reinforcing fiber; a second thickness of structural foam, and a third thickness of resin matrix and reinforcing fiber; the third thickness disposed between the first and second thicknesses. A reinforcing side element optionally can be installed in any flank.
In another aspect, processes for making structural elements are provided. The processes generally include selecting a mandrel of a desired shape, filament winding reinforcing fiber with a resin matrix onto the mandrel resulting in a length of uncured filament wound component stock on the mandrel, curing the length of filament wound component stock, removing the mandrel from component stock, and forming a plurality of structural elements from the component stock.
The process can also be performed by selecting a mandrel of a desired shape, filament winding a first thickness of reinforcing fiber with a resin matrix onto the mandrel, placing a thickness of structural foam onto the first filament wound thickness, filament winding a second thickness of reinforcing fiber with a resin matrix onto the mandrel resulting in a length of uncured filament wound component stock on the mandrel, the component stock having a first filament wound thickness, a second filament wound thickness, and a structural foam thickness disposed between the first and the second filament wound thicknesses. The length of filament wound component stock is cured, removed from the mandrel, and a plurality of structural elements are formed from the component stock.
Bicycle frame components can be prepared by manufacturing structural components by selecting a mandrel of a desired shape, filament winding a first filament wound thickness of reinforcing fiber with a resin matrix onto the first mandrel, placing a thickness of structural foam onto the first filament wound thickness, filament winding a second filament wound thickness of reinforcing fiber with a resin matrix onto the mandrel to form a length of uncured filament wound component stock on the mandrel. The component stock typically has a first filament wound thickness, a second filament wound thickness, and a structural foam thickness disposed between the first and the second filament wound thicknesses. The length of filament wound component stock is cured, removed from the mandrel, and formed into a plurality of structural elements. Cap elements can be prepared by selecting a mandrel of a desired shape, filament winding reinforcing fiber with a resin matrix onto the mandrel to form a length of uncured filament wound cap stock on the mandrel, curing the length of filament wound cap stock, removing the mandrel from the cap stock, and forming a plurality of structural elements from the cap stock.
In another aspect, a method for constructing a frame for a vehicle having at least two wheels is provided. The method generally includes: obtaining a three-sided front structural element; obtaining a rear structural element; obtaining a head tube, a head cap, a seat tube, a seat cap, a bottom bracket tube and a bottom bracket cap; joining the rear structural element to the front structural element; joining the head tube to the front structural element with the head cap; joining the seat tube to the front structural element with the seat cap; and joining the bottom bracket tube to the front structural element and the rear structural element with the bottom bracket cap.
In another aspect, a method is provided for constructing a frame for a vehicle having at least two wheels. The method includes filament winding a continuous front structural element that includes a top beam, a seat beam, and a down beam that are connected. A rear structural element is also filament wound, the rear structural element including a seat stay, a chain stay, and mounting protrusions. Also provided are a head tube, a head cap, a seat tube, a seat cap, a bottom bracket tube, and a bottom bracket cap. The rear structural element is joined to the front structural element. The head tube is joined to the front structural element with the head cap. The seat tube is joined to the front structural element with the seat cap. The bottom bracket tube is joined to the front structural element and the rear structural element with the bottom bracket cap.
In another aspect, a method is provided for manufacturing a bicycle fork leg element. The method generally includes selecting a mandrel of a desired shape, filament winding a thickness of reinforcing fiber with a resin matrix onto the mandrel to form a length of fork stock, curing the length of filament wound fork stock, removing the mandrel from the fork stock, and forming a plurality of fork leg elements from the fork stock. A method for manufacturing a fork leg element can include selecting a mandrel of a desired shape, filament winding a first thickness of reinforcing fiber with a resin matrix onto the mandrel, placing a thickness of structural foam onto the first filament wound thickness, filament winding a second thickness of reinforcing fiber with a resin matrix onto the mandrel, curing the length of resulting filament wound fork stock, removing the mandrel from the fork stock, and cutting a plurality of fork leg elements from the fork stock.
In another aspect, a method for manufacturing a bicycle component is provided that includes selecting a mandrel of a desired shape, filament winding a thickness of reinforcing fiber with a resin matrix onto the mandrel to form a length of wet component stock, removing the mandrel from the wet component stock, making a cut along the wet component stock, placing a portion of the component stock on a mold, causing the portion to component stock to substantially conform to the shape of the mold, curing the portion of component stock in place on the mold, and removing the portion of component stock from the mold, resulting in a molded, cured component.
In another aspect, a fork for a vehicle is provided. The fork generally includes a steer tube having an elongate tubular main steer tube section, an upper insert in the main steer tube section, a crown having an upper receptacle and one or more a lower receptacles. One or more leg members are installed into the lower receptacle(s). In certain embodiments, the steer tube can further include a reinforcing sleeve installed into the main steer tube. The main steer tube and/or the reinforcing sleeve can be filament wound components. The leg member can be, for example, a resin matrix and reinforcing fiber and can be a filament wound component. The upper portion of the insert optionally can be threaded. The lower portion of the reinforcing sleeve also can be threaded.
In certain embodiments, the leg member can be formed as a upper half leg and a lower half leg The upper half leg optionally can be more rigid than the lower half leg. In another embodiment, the leg member can include an upper leg, a mid half leg, and a lower leg. The fork leg or portions thereof can be, for example, resin matrix and reinforcing fiber, such as a filament wound component.
In another aspect, a fork for a wheeled vehicle is provided. The fork includes a steer tube, a first leg member, and a second leg member. Each leg member has a mounting protrusion that is installed into a receptacle in the steer tube. A leg member can optionally be formed as a first thickness of resin matrix and reinforcing fiber, a second thickness of resin matrix and reinforcing material, and a third thickness of structural foam disposed between the first thickness and the second thickness.
In a related aspect, another fork for a wheeled vehicle is provided. The fork includes a steer tube; a crown; and a unitary fork leg member. The unitary fork leg member has a center mounting section joining a right fork leg and a left fork leg. In a certain embodiment, the unitary fork leg member includes a first thickness of resin matrix and reinforcing fiber, a second thickness of resin matrix and reinforcing material, and third thickness of structural foam disposed between the first thickness and the second thickness.
A further understanding of the nature and advantages of the invention will become apparent by reference to the remaining portions of the specification and the drawings.